Limb amputations have been part of humankinds' existence from its beginning as evidenced by hieroglyphics depicting techniques to fashion amputee prosthetics. Traumatic limb amputations were a common battlefield wound in the age of combat fought with swords and axes. Cautery of the residual limb or stump with hot oil or heated metal was the preferred method to stem the flow of blood on these ancient battlefields. It was not until the 1500's when Ambroise Pare demonstrated that ligation of the artery and vein with delayed or primary closure of the amputee wound provided superior healing and rehabilitation when compared to the cauterization techniques. Injury to or loss of extremities on the modern battlefield are particularly common today and is seen in 70.5 percent of all wounded soldiers. Within this group, 7.4 percent experienced amputation with explosive devices (explosive shock waves and shrapnel) accounting for 87.9 percent of the mechanism of injury.1 Sadly, as the manner in which humankind maims itself on the battlefield has advanced, the management of amputations has changed little since Pare's revolutionary surgical management techniques. Amputations though are not unique to the battlefield. For civilians, in one study, the major traumatic reasons for lower extremity amputations involved blunt or penetrating trauma with motor vehicle accidents and gunshot wounds the two most common causes respectively.12 Further, according to the National Limb Loss Information Center, vascular disease is the leading case of lower extremity amputation in the United States with trauma second. Overall, approximately 30 percent of all amputations are of a lower extremity.2 As of 2005, approximately 1.6 million people lived with the loss of an appendage and this number is expected to double by 2050.13
One of the most difficult problems that a lower extremity amputee faces today is being able to transition to the use of a new prosthesis quickly. In some cases, patients take years to functionally adapt to their prosthesis. This delay in the use of the prosthesis is often due to the physiological changes that occur in the extremity during healing and afterwards during normal daily activities. This transition to use is further complicated by the skin covering the stump and the boney prominences within the stump preventing comfortable and consistent use of the prosthesis because the skin covering the amputation is not physiologically or anatomically suited for the pressures involved in ambulation. As a result, 25 percent of patients experience ulcerations of the stump and delayed wound healing from this physiological and mechanical skin mismatch on the amputee stump. Use of the prosthetic is further limited by pain and discomfort in the stump caused by the prosthesis, with amputees receiving on average a new prosthesis every two years.3 
These problems are further complicated by marked variation in the surgical amputation techniques and socket manufacturing processes, both of which are typically performed by skilled artisans. Regardless of how advanced the prosthesis may be, if the amputee cannot use it because the stump is prepared anatomically and physiologically incorrect, then it is worthless. For these reasons, it seems evident that attempts to reconstruct or transplant the evolutionarily adapted weight-bearing and friction-tolerating glabrous skin of the foot to the amputee stump would help prevent these complications.
The successful use of vascularized plantar glabrous skin free flaps in reconstruction of like skinned areas has been documented, including its use on a below the knee amputation (BKA).4,5,6 These successes have been achieved because the vascular anatomy of the foot and its plantar surface (i.e., sole of the foot) have been well documented through dissection and angiographic studies.7,8,9,10,11 These studies have demonstrated that the glabrous skin and deep muscles of the plantar surface of the foot receive their blood supply from the posterior tibial artery (PTA) and its distal divisions—the medial and lateral plantar, plantar arch and metatarsal branches. The PTA also supplies the medial calcaneus region and has lateral anastomatic connections with the external Calcanean, the terminal branches of the posterior Peroneal artery (PPA) through the PTA's internal Calcanean branches. Distally the Communicating artery from the Dorsalis Pedis artery passes between the first two heads of the Dorsal Interosseous muscle then joining with the Plantar Arch. Typically, this artery is ligated as it is encountered during the development of the plantar flap, just proximal and between the first and second metacarpal-phalangeal joints.
It is equally important to consider reconstruction of the hydrodynamic function of the skeletal system after amputation. With the loss of the fluid filled ankle joint in below knee amputations and the loss of the knee joint and ankle joint in above the knee amputations, the normal non-compressible fluid hydraulic system of the axial skeleton is lost. As a result, expecting the amputee to walk on a boney stump inserted into a prosthetic socket can be unreasonable, as evidenced by the difficulty often experienced with the transition and use of a new prosthesis.
In addition to the problems of learning to walk with a prosthesis, the methods and devices used to hold the prosthesis in place on the residual limb present a whole different set of problems. The manner in which a prosthetic device is attached to the residual limb can determine the amount of control the amputee has over the prosthesis and, consequently, their ease and range of movement. Patients have utilized a variety of belts, bands, straps, cuffs, harnesses, sockets, suction sleeves and the like to secure a prosthesis against a residual limb. The disadvantage with most of these devices is that they are inconvenient and usually cause chafing, which leads to sores and abrasions and, in some cases, secondary skin infections. They can also impair circulation in the residual limb causing pain and tissue degradation. Other techniques involve the use of protruding skeletal extensions, where a rod or other mechanism is affixed to the terminal bone end of the residual limb. The extension protrudes from the residual limb to be attached to a prosthetic device. The challenge with these devices is the difficulty in attaining a permanent intact skin-prosthesis interface. If the tissue does not heal properly around the extension, the exit wound can remain open and subject to infection and other problems.
There is a need to overcome the dysfunctional, post-surgical-anatomical deficiency exhibited by most currently used prostheses. More specifically, there is a need for a system that replaces that portion of the non-compressible fluid hydraulic system lost with amputation. Such a system should distribute the weight and forces of ambulation over a larger area of the residual limb end. There is also a need for an improved plantar surface free flap harvesting technique, which will provide the proper weight bearing skin of the plantar surface to the residual limb. Finally, new methods and devices are needed for securing a prosthesis to a residual limb.